Table 1.

Change in leisure-time physical activity (LTPA; min/week) from 11 to 15 years according to potential predictors; 1993 Pelotas (Brazil) birth Cohort Study, 2004–2008 (n 4120)

	Model 1*								Model 2†
	Boys				Girls				Boys			Girls
Predictor	n	Mean	95 % CI	P value	n	Mean	95 % CI	P value	Mean	95 % CI	P value	Mean	95 % CI	P value
Skin colour				0·01				0·04			0·08			0·09
White	1301	51	19, 82		1334	−60	−77, −42		55	23, 88		−59	−77, −41
Mixed	344	131	69, 193		391	−14	−47, 19		112	49, 175		−15	−50, 19
Black	296	143	76, 210		297	−32	−70, 5		132	62, 201		−47	−86, −8
Socio-economic level				<0·01‡				0·25‡			0·01‡			0·54‡
Poorest	668	121	77, 165		645	−36	−62, −10		124	78, 169		−46	−73, −20
Intermediate	622	75	30, 121		707	−43	−67, −18		77	30, 124		−43	−68, −19
Wealthiest	670	24	−17, 71		668	−57	−83, −32		30	−16, 76		−58	−84, −32
Mother's LTPA change				0·02‡				0·01‡			<0·01‡			<0·01‡
Always zero	1366	56	25, 87		1404	−51	−69, −33		48	15, 81		−62	−81, −44
Decreased	303	77	11, 143		337	−51	−87, −14		85	17, 154		−47	−84, −10
Increased <150 min/week	170	143	55, 231		172	−26	−78, 26		169	79, 259		−26	−78, 25
Increased ≥150 min/week	227	135	58, 211		237	12	−32, 55		156	77, 234		15	−29, 59
Exposure during growing-up				0·05				<0·01			0·04			0·01
Mostly indoors	1399	59	28, 89		1631	−55	−71, −38		59	27, 91		−59	−75, −42
Mostly outdoors	617	114	68, 160		462	3	−28, 34		119	70, 167		−9	−41, 22
Fear of living in neighbourhood				0·87				0·06			0·92			0·24
Never	1604	74	46, 103		1481	−55	−72, −37		77	48, 107		−57	−75, −40
No longer	216	95	18, 173		247	−24	−66, 18		90	9, 171		−20	−63, 23
Developed	128	41	−60, 142		239	−17	−60, 25		45	−62, 152		−36	−80, 7
Always	68	77	−61, 216		127	14	−44, 72		94	−57, 244		−13	−74, 47
BMI status at 11 years				0·48‡				0·11‡			0·76‡			0·10‡
Normal	1510	77	48, 107		1636	−47	−63, −30		89	51, 127		−49	−66, −32
Overweight	199	105	24, 186		276	−47	−86, −7		138	41, 236		−36	−79, 6
Obese	313	43	−21, 108		181	3	−46, 52		93	16, 170		−2	−55, 50
Sexual maturation in quartiles				0·02‡							<0·01‡
1 (least)	494	61	10, 111		–	–	–		48	−5, 101		–	–
2	380	91	33, 148		–	–	–		95	36, 155		–	–
3	258	81	12, 151		–	–	–		98	24, 171		–	–
4 (most)	200	197	117, 276		–	–	–		212	128, 297		–	–
Age of menarche								0·07						0·04
Before 12 years	–	–	–		616	−61	−88, −35		–	–		−71	−99, −45
12 years or older	–	–	–		1397	−32	−50, −14		–	–		−36	−54, −18
Screen time change in tertiles				0·11‡				0·70‡			0·22‡			0·55‡
Least	630	44	−1, 89		751	−34	−58, −10		61	2, 120		−40	−65, −14
Intermediate	647	84	39, 129		730	−65	−89, −40		110	53, 167		−70	−95, −45
Highest	729	95	52, 137		613	−24	−51, 3		112	59, 165		−26	−53, 2
Total	2023	75	49, 100		2097	−42	−57, −28		96	64, 128		−43	−58, −28

*Adjusted for baseline PA level (min/week) and follow-up duration (months).

†Adjusted as in Model 1 plus predictors in the same level or the levels above.

‡P value for linear trend.